DISTRIBUTED SYSTEMS -
Jan M. RabaeyDonald O. Pederson Distinguished Prof.
Director FCRP MultiScale Systems Center (MuSyC)
Scientific Co-Director Berkeley Wireless Research Center
University of California at Berkeley
INTEL, FEBRUARY 23 2011
The Next Grand Challenge in Embedded System Design
Infrastructural
core
The Swarm and the Cloud
TRILLIONS OF
CONNECTED DEVICES
[J. Rabaey, ASPDAC’08]
THE
CLOUD
THE SWARM
The New Moore’s LawStill … Improve functionality per unit cost to create
whole new application areas,
But in a brand new setting
1970
Mainframes
1980
PCs
1990
Internet
2000
Wireless &
Personal Devices
2010-
Cloud
Computing
Immersive User
Experiences
Ubiquitous
Sensing
The Swarm Perspective
It’s A Connected WorldTime to Abandon the “Component”-Oriented Vision
Moore’s Law Revisited:
Scaling is in number of connected devices,
no longer in number of transistors/chip
[MuSyC 2009]
The functionality is in the swarm!
Resources can be dynamically
provided based on availability
One Vision: CyberPhysical
SystemsLinking the Cyber and Physical Words
[H. Gill, NSF 2008]
Another One: BioCyber (?) SystemsLinking the Cyber and Biological Worlds
Examples: Brain-machine interfaces and body-area networks
The Cloud and the Swarm
Distributed Sense and Control Challenges
Complexity
Modeling/
Abstractions
System
Metrics
(ENERGY)
Run-time
Management /
Diagnostics
Verification
Security/Tru
st
Robustness/
Reliability
Failure to Address in
Fundamental and
Cohesive Way will
Slow Down or Prohibit
Adoption
It’s All About Energy
Energy among most compelling
concern of distributed IT platform and
its applications.
Mobiles
Smart grid
Avionics
Human-centric
systems
OUR VISION: Distributed
Sense and Control Systems
to Dynamically Enforce
Energy-Proportionality
Business as Usual Will Not Do
The mantra’s of two decades of low-power design:
slow, simple, many, dedicated, adaptive
While some opportunities are left, concepts now commonly exploited
The end of voltage and
energy scaling !?
Unless novel devices are adapted soon …
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Vdd (V)
En
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rm.)
Total
Switching
Leakage
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VDD (V)
0.001
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Energ
y (n
orm
.)
0.3V
12x
In Need of Novel
Architectural Ideas
The Golden Opportunity
Energy-efficiency of most systems decreases under reduced loads
Energy-Proportional Computing
Thro
ughput Actual
Ideal
Power
Courtesy:
L. Barroso, Google
Computation and Energy
Throughput
Power
Actual
Ideal
DOING NOTHING (or
LITTLE) WELL
Energy efficiency of most systems degrades
under reduced load conditions
How we design systems
How nature designs systems
[* Term coined by L. Barroso, Google]
A Generic Concept
Throughput
Po
we
r
Actual
Ideal
DOING NOTHING (or
LITTLE) WELL
Conceive and Enable Systems that are Energy-Proportional over Large Throughput Range. Applies to all aspects of the IT Platform!
Not the case in today’s systems (computing, storage, communication)
The Big Picture
Hugely Scalable Platforms“Providing computation/computation at the optimal
energy”
Attention-Optimized
Computing/Communication“Matching computation to desired utility”
Utilit
y
Maxim
ization
A Closed Loop System
The Cloud/Swarm
Challenge
Trade off computation and communication in light of limited energy, communication and,
computational resources so that desired utility is reached under highly variable conditions and loads
Requires scalable distributed optimization strategy
The “Playground”
A continuously changing
alignment
(environment, density, activity)
The Swarm/Cloud Operating System -Dynamically trading off resources
The Swarm/Cloud Services and Applications
“What matters in the end is the utility
delivered to the user”
Utility Maximization
Distributed Resources
Communication
(Spectrum)Computation Sensing
ActuationStorage Energy
ADDRESSING THE
CHALLENGES
17
Focus Center Research Program
Features
Multi-university teams
Focus on topics where evolutionary R&D is insufficient
Emphasis on discovery; long-range time horizon
Large-scale effort (~ $7M per center annually)
Equal cost sharing between industry & government
Access to relevantly trained graduate students
“The (SRC) focus center program is designed to create a nationwide, multi-university network of research centers that will keep the United States and U.S. semiconductor firms at the front of the global microelectronics revolution.”
Craig R. BarrettRetired Chairman of the Board, Intel
Former Chair, Semiconductor Technology CouncilRecent Chair, FCRP Governing Council
MUSYC IN A NUTSHELL
Grand Goal:
Grand Challenge:
Create comprehensive and systematic solution the
distributed multi-scale system design challenge.
“Energy-smart” distributed systems, that
Are deeply aware of balance between energy availability and
demand
Adjust behavior through dynamic and adaptive optimization at
all scales of design hierarchy.
Common Core:
20 Faculty Distributed over 10 US Universities
SCS Theme
Distributed sense and control systems.
Target: Airborne Platforms (Avionics)
LSS Theme
Large-scale “energy-intensive”
systems
Target: Data centers
SSS Theme
Small-scale “energy-frugal” systems
Target: Human-centered networks for
augmented sensing (e.g. BMI)
Exploring the multi-scale space:
THE MUSYC TEAM
SCS
LSS
SSS
Including experts in petascale computing, networking, control, signal
processing, information theory, avionics and neuro-engineering
THEME 1: DISTRIBUTED SENSE AND CONTROL SYSTEM METHODOLOGY (A. SANGIOVANNI-VINCENTELLI)Address challenges in complex distributed control systems by employing structuredand formal design methodologies that seamlessly and coherently combine variousdimensions of multi-scale design space, and that provide appropriate abstractions tomanage inherent complexity.
Case study: Avionics
Complexity
SCS DRIVERS AND METRICS
Today Power sources/sinks
Electric distribution
Control system
• # power sources ~1• # loads ~100• peak power ~ 400kW
• # power sources ~ 10• # loads ~1000• peak power ~ 4MW
Tomorrow
Large Airborne Platforms
In Line with DARPA META Program
Reduction of development time of complex, distributed control systems by 2X through increased use of formal methods for specification, design and verification. Reduction of the number of faults that require the system to be taken out of service for inspection or repair by 2X, through the increase used of onboard models and dynamic reconfiguration to provide enhanced fault tolerance.
SCS HIGHLIGHT: FORMULATED DESIGN FLOW FOR DISTRIBUTED AVIONICS SYSTEMS
Platform-based design enables architecture exploration (tradeoff weight, stability, …)
Power SystemArchitecture
Control System Architecture
Hardware, Software, Communications
Redesign
Incremental conservative design• Steady state worst case power draw• 2x overdesign results in weight penalty
Dynamics problems identified in verification
Communications latency impacts stability
Dynamics, control, communication latency addressed in all layers
Current State of the Art
Robust design for distributed control system
Ptolemy, Metro tools enable robust design of complex dynamical systems
Our Approach(STRONG impact on META I and II BAA)
Collaboration with UTC (HS), IBM and Raytheon
Contributors: E. Lee, R. Murray and ASV
Realistic Test Benches under development
THEME 2: LARGE-SCALE SYSTEMS (T. SIMUNIC-ROSING)
Realize distributed closed-loop power-management strategies that result in “energy-intensive” large-scale systems to be orders of magnitude more energy-efficient, whileensuring that mission-critical goals are met. To be accomplished by employing holisticmulti-scale solution including all components of the system at multiple hierarchy levels.
Target: Data centers
“Doing nothing well”
LSS DRIVERS AND METRICS
SOLUTION: Distributed and hierarchical management that ensures that energy is only consumed if, when and where needed.
Enable “energy-proportional” computing, and to “do nothing well” in Datacenters and Cloud Computing
METRIC: Datacenter Energy Efficiency
Barroso & Hölzle, 2009
LSS HIGHLIGHT: ENERGY-AWARE LOAD
SCHEDULING
BWorkload Model/
Predictor
Energy AwareWorkloadScheduler
ClusterManager
Building/Facility ManagerTasks
SLAs
Energy Supply Information
Energy Consumption
Application Resource Footprint
Contributors: Katz, Snavely, Rosing, NSF GreenLight
Cooling-aware management
THEME 3: SMALL-SCALE SYSTEMS (D. JONES)
Explore absolute bounds of energy-efficiency and miniaturization in “energy-frugal”human-centric distributed IT systems, through distributed management strategy thatdynamically and adaptively selects correct operational point corresponding to varyingapplication needs in terms of accuracy or resolution.
Target: Augmented sensing in humans (BMI)
SSS DRIVERS AND METRICSKEY METRIC: UTILITY/ENERGY
Utility Maximization• Define system performance in terms of user/application relevant utility• Dynamically optimize algorithms and platforms to maximize utility
Explore, analyze, and implement advanced closed-loop learning systems in brain-machine interfaces
In collaboration with UCB Neuroscience and UCSF Neurosurgery
ScalableSignal
acquisition
Utility-OptimizingScalable Systems
Management
HugelyScalable
Processor
AttentionalAlgorithms
ScalableRadio
Frequency Tx and Rx
RF EnergyHarvesting
EfficientIntegrated
MicroscopicAntenna
Voltage ScalablePower Source
3D Integrated Packaging
HUGELY SCALABLE SSS PLATFORM
3 10 700.00
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in [
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Stage depth [fo4]
20f
25f
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Eto
tal
[J]
3
3
SSS HIGHLIGHT: HUGELY SCALABLE BMI
PLATFORMSContributors: Rabaey, Blaauw, Franzon
3D Inductors promising higher L, Q
Energy-neutral wireless link delivers energy-proportionality over broad performance range from scavenged power
3
1 mm
65 nm CMOS, in fab
[Franzon]
[Rabaey]
Low-Jitter Timers for Power Control
[Blaauw]
1.4 μJ/hour
IBM 130 nm CMOS
In Summary …
The Laws of the Cloud and the
Swarm In a connected world, functionality arises
from connections of devices.
Largest efficiency gain obtained by
balancing available resources:
computation, communication and energy.
The dynamic nature of the environment,
the needs and the resources dictate
adaptive solutions.
No one wins by being selfish.
Cooperation and collaboration are a
must.
MuSyC as a Collaborative Answer to the
Swarm and Cloud Challenges